Carburetor

ABSTRACT

Carburetor for gasoline engine has connecting air-intake and gas mixture chambers separated by an adjustable, air-metering valve provided with throttle opening means of variable flow area and communicating with said connecting chambers for providing venturi effect. Gas metering member in gas mixture chamber adjustable with movement of valve to vary amount of gas globules metered out to mix with air throttled through the opening means in valve, according to demand of engine. Efficiency of carburetion improved by controlled suction of air at any given throttle opening, for combination with likewise controlled flow of gas globules, in a proportion with reference to said venturi effect which provides maximum power and performance efficiency at any given engine speed, while accomplishing substantially complete atomization of the gas globules at all engine speeds.

Elite Chapman 14 1 Dec. 17, 1974 CARBURETOR [76] Inventor: Donald L.Chapman, 191 Osceola Ave., Tallmadge, Ohio 44278 22 Filed: Oct. 16, 197221 Appl. No.2 298,187

[5 6] References Cited UNITED STATES PATENTS Primary Examiner-Tim R.Miles 5 7 ABSTRACT Carburetor for gasoline engine has connectingairintake and gas mixture chambers separated by an adjustable,air-metering valve provided with throttle opening means of variable flowarea and communicating with said connecting chambers for providingventuri effect. Gas metering member in gas mixture chamber adjustablewith movement of valve to vary amount of gas globules metered out to mixwith air throttled through the opening means in valve, accord- 2,681,2166/1954 Knecht 261/78 R ng to em n of ngine. E ficiency of Carburetionim- 2,756,033 7/1956 Smithet a] 261/44 R proved by controlled suction ofair at any given throt- 3,026095 3/ 6 amm llt a 261/50 R tle opening,for' combination with likewise controlled 3,086,758 4/1963 Greene 261/44R fl f gas globules in a proportionwith reference to 33360l4 8/1967 h261/44 R said venturi effect which provides maximum power 3350073 0/1967261M412 and performance efficiency at any given engine speed, 3.40695210/1968 White 26l/5OA h.] I. hi bt -t. H I t at 3,424441 1/1969 Caisleyet a1 ...J261/50 A t accompls S Comp 3.472495 10/1969 Marsee et a].261/76 Ofthe gas globules at engme Speeds- 3 493,2l7 2/1970 Farley261/44 R 1 3.709.469 1/1973 Edmonston ct 111. 261/44 R 3 6 Drawmgfigures I /E 3 /5 f 7 9 W I 22b /29 i V I f 1 /O v 9 Z2 v v Q 7 M L 4- Ii i /6 C) 0 Q 6- T1 1 p- -11rv K I KKK 4 I2 1 j I PATENTED DEC] 7 I974SHEET 2 BF 3 PATENIED BEE 71974 sum 3 o 3 CARBURETOR BACKGROUND OFINVENTION Heretofore, carburetors, as for gasoline engines, have been ofa general type including a device for sending air through or over aliquid fuel, so as to produce an explosive mixture. In other words, theprocess of carburetion includes charging air with hydrocarbon, such asgasoline in finely divided liquid form, whereby the resulting gasglobules can be burned for production of energy. In spite of the vastnumber of improvements heretofore made in conventional carburetors, eventhe best of them have been inefficient in atomizing the gas globules,and in fact they only slobbered the gas out, especially at partialthrottle. Such carburetors, have to a large extent, been unsatisfactorybecause when they were large enough for a given purpose they were toolarge for maximum efficiency at partial throttle, and when they were onthe small side they were not sufficiently sensitive to accomplish goodatomization of the gas but were too restrictive for accomplishing peakpower performance.

SUMMARY OF INVENTION The present invention relates to an improvedcarburetor, as for a gasoline engine, by which maximum operatingefficiency is accomplished by accurately controlling the effectiveatomization of the gas globules with reference to selectively variablesizes of aventuri opening in the carburetor. For the purpose ofefficiently controlling the mixture of the air and gas globules, inproportion to the degreeof power required by an operator of the engine,a speed controlling accelerator is operable to shift a valving memberacross a passage between connecting air-intake and gas mixture chambers,selectively to vary the effective flow area of a throttle opening in thevalving member, so that as the demand for power is increased, the flowarea of the throttle opening is proportionately increased. With suchopening movement of the valving member a gas supply tube, carried by thevalving member and connected to a source of the gas, is likewiseproportionately moved' with reference to a metering device located withthe gas mixing chamber, to meter out the gas in requisite proportion tothe changes in flow area of the throttle opening. Thus, by varyingthe'flow area of the venturi opening, the air pressure is variedproportionately and the speed of the air, and consequently that of thegas, is also varied. To this end, the gas metering device may includerelatively movable parts which are operable by movement of the valvingmember to control the amount of atomized gas metered into the mixingchamber, in predetermined precise relationship to the controlled flow of'air through the venturi opening to the mixing chamber. This gasmetering device is particularly adaptable for mixing the. gas globulesand air, self-adjustably' according to the requirements at variousspeeds of engine operation, to accomplish complete ignition andutilization of the gas globules at all such speeds.

Objects of the invention, other than as described above, will bemanifest from the following brief description and the accompanyingdrawings.

Of the accompanying drawings:

FIG. 1 is a top plan view of a carburetor embodying the features of theinvention.

DESCRIPTION OF THE INVENTION Referring to FIGS. 1 to of the drawingsgenerally, and to FIGS. 3 to 5 in particular, the numeral desig nates acarburetor, embodying the features of the invention, mounted on anengine block B (see FIG. 2) and including a tubular housing 11 havingintegral flange means 12 for securing the vsame on block B, thereby toalign a passage 13 through the housing with a passage 14 in the block Bfor connecting with a comof plate 18 to the bustion chamber (not shown)of the engine.

The carburetor 10 may comprise top and bottom sections 15 and 16,including complementally connected,

lateral extensions 15 and 16 thereof in a plane at right angles to thecentral axis of the tubular housing 11, and

defining laterally spaced guide slots l7, l7 forslidable reception ofspaced side edges of a slide-valve plate 18, said plate serving todivide the passage 14 into an outer air-intake chamber 19 and an innergas-mixing chamber 20. The plate 18 is provided with a throttle aperturemeans 22 therethrough, adapted to have a variable effective flow area,presented within the mixing chamber 20, the flow area being varied bysliding adjustment of the slide plate. As best shown in FIG. 4, theover-all size of the throttle aperture means 22 may be relatively large,with converging sides 22a thereof cooperating with the passage 14 ofchamber 20 thereby defining a relatively small, generally triangular,air-throttling opening communicating with the axially aligned chambersl9 and 20, which triangular opening can beselectively enlarged ineffective flow area by said movement right in the condition shown inFIGS. 1 to 5. I Affixed to the slide plate 18, exteriorly of the tubularhousing 11, to be movable with said plate, may be a fluid-gas supplytube 23 which extends through the wall 16a of the bottom section- 16,below plate 18, and is slidably received through a-perforated,gas-metering tube 24, suitably affixed between diametrically oppositewall portions of the passage 13, to be in otherwise fluid sealedrelation thereto. Fluid gas may be supplied to the tube 23 from a sourcethereof (not shown), through flexible tubing 23a and the gas flow fromthe supply tube 23 into mixing chamber 20 is adapted to be automaticallyadjusted or varied by any sliding movement of the slide plate 18.

' To this end, a free end of the gas-metering tube 24 within the tube23, may be provided "with a suitable opening 24a for centered receptiontherethrough of a tapered metering needle 25, which is selectivelyadjustably afiixed to the passage wall 13. The arrangement is such thatin all positions'of axial sliding movement of thegas supply tube 23 withreference to the tapered needle 25, gas supplied through said tube 23exits into the adjusted, enclosed space 27 at the corresponding end ofthe metering tube, to be sucked through one or more uncovered apertures28, 28 of one or more series thereof extending longitudinally along thewall of the metering tube 24 (see FIG. 5).

Accordingly, in all axially adjusted positions of the gas supply tube 23and with all effective diameters of the tapered needle presented throughthe hole 24a in the exit end of the supply tube, the fixed metering tube24 accurately controls the amount of gas'being metered out directly inproportion to the amount and speed of the air rushing through theeffective venturi opening 22b, the variable flow area of which openingis controlled by the speed, or power required to be obtained from theengine. A V-shaped hood or shield 29 may be affixed in the throttlepassage 14 to overlie the length of the gas-metering tube 24, fordeflecting the air rushing through venturi opening 22b, uniformly topass around said metering tube.

In use of the improved carburetor shown in FIGS. 1 to 5, in conjunctionwith a gasoline engine, having a known type of manually operableaccelerator means for controlling the speed of the engine, theaccelerator (not shown) is operable through the rod 30 to enlarge theeffective flow area or size of the venturi opening 22b, by slidingmovement of the plate 18 in the guide slots 17 to the right from theposition of the plate as shown in FIGS. 1 and 2. This movement, inaddition to enlarging the effective flow-area of the venturi opening22b, also enlarges the flow-area of the gas-metering opening 24a in theadjusted gas supply tube 23, as well as exposing one or more additionalholes 28 in the gas metering tube 24 for passage of additional gas fromthe supply tube into the path of the larger amount of air being suckedthrough the enlarged venturi opening 2211 as described above.

In use or operation of the improved carburetor, described above inparticular reference to FIGS. 1 to 5, with a gas-operated,internal-combustion engine, air is in known manner sucked into theair-intake chamber 19, through the adjustably effective venturi opening22b of slide-valve plate 18, and into the mixing chamber 20, to bethoroughly mixed with combustible gas globules or particles exuded orsucked from the aperture 28 at the discharge end 24 of tube 23 carriedby the slidable plate 18. In other words, liquid gasoline is drawn intothe air-intake chamber to be intimately mixed with the air rushingthrough the selectively adjusted venturi opening 22b as a relativelyfine spray, generally in a ratio of about one part of gasoline by weightto fifteen parts of air, for example. The amounts and proportions ofgasoline and air mixture which passes through the carburetor is, for themost part, variably controlled by an accelerator (not shown) which inturn adjusts the sliding movement of valve plate 18 carrying the gastube 23 with it.

As the mixture leaves the carburetor 10, it is drawn into enginecylinder or cylinders (not shown), where it will be exploded by ignitionmeans in known manner. It is known, however, that even the bestavailable carburetors have not been capable of accomplishing completeatomization of the gas globules. In other words, the gas globules werenot completely consumed upon ignition of the same in the enginecylinders at some, if not all, acceleration speeds of operation of theengine. Complete atomization is accomplished by the improved carburetor,at all acceleration speeds, by selectively proportioning of the amountof gas metered into the gas and air mixing chamber 20. With a small,slowspeed setting of venturi or throttling opening 22b, generally asshown in FIGS. 3 and 4, a carefully measured,

relatively small amount of gas is sucked from the end of the gas supplytube 23 by the proportionately effective amount of air sucked throughthe venturi opening. Accordingly, the amount of liquid gas sucked intothe air passing through the gas and air mixing chamber 20 is soefficiently atomized that it can be accurately controlled by apreadjusted size of the venturi opening 22 b. That is, theself-adjusting nature of the gas and air mixing structure shown anddescribed is such that maximum speed or acceleration rate of the engineis possible with a minimum of gas consumption, as well as withaccomplishment of complete atomization of the ignited gas globules.

In use of the improved carburetor for some purposes, reduction of theair speed into the air and gas mixing chamber 20 may be desirable tosave gas while attaining maximum power. To this end, and in reference tothe modification shown in FIG. 6, which corresponds substantially toFIG. 4, the speed of the air passing through the venturi opening 22b inthe slide-plate 18 may be reduced by diverting a proportionate amount ofthe air from entry into the mixing chamber 20. This diversion of airpassing through the effective opening 22b may be accomplishedautomatically as by means of the modified form of slide plate 18 shownin FIG. 6, wherein plate 18 is provided with a series of holes 31, 31,extending in longitudinally spaced relation from at least one inner edge22a of the plate 18, defining the adjustable size of the venturiopening. 22b, to a passage 32 connecting with a tube33 from a vacuumoperated,

' accelerator controlled valve or motor 34 which,

. chambers, a slide-valve member, adjustably mounted through a suitablelinkage (not shown) to the slidecontrol rod 30 (see FIG. 3), adjusts thesize of said venturi opening as well as the amount of gas being mixedwith air passing through the same. As an example, in operation of anengine at high speeds the carburetor can be self-operating, by thehigher speeds of the air being sucked through the venturi opening 22b,correspondingly to reduce the size of the venturi opening and at thesame time control the amount of gas fed through the same. It would bepossible, for example, I

through variations in the number of openings 31 exposed in the effectiveventuri opening 22b, to calculate and provide appropriate spacing andsizes of the gas metering openings 28 in the metering tube 24, therebyto attain maximum economy of gas use at the high speeds which heretoforewould have resulted in unburned gas with the use of the prior artcarburetors.

Other modifications of the invention may be resorted to withoutdeparting from the spirit thereof or the scope of the appended claims.

What is claimed is:

l. A carburetor as for a gasoline engine, comprising: a housing havingconnecting air-intake and gas-mixing between said chambers, and having aventuri-aperture means of variable flow area therethrough, for passageof air from said air-intake chamber to said gas-mixing chamber withcorrespondingly varying venturi effect on said air; means for adjustingsaid slide-valve member to vary the flow area of said venturi aperturemeans. and a gas metering device presented within said gasmixingchamber, for supplying gas to said gas-mixing chamber for convergencewith said air passed through said venturi aperture means; said gasmetering device said relatively fixed tube, to open and close one ormore said gas metering holes to said gas mixing chamher, said gas supplytube having a gas outlet orifice in a free end thereof presented withinsaid gas mixing chamber; and a tapered stem being affixed to saidhousing to extend into said gas supply tube through said outlet orificeto vary the effective gas flow area thereof in proportion to relativemovement of the supply tube.

2. A carburetor as in claim 1, an air deflecting hood being providedabove in said relatively fixed tube for dispersing the air passingthrough said venturi-aperture means, and uniformly around the fixedtube.

3. A carburetor as for a gasoline engine, comprising: a housing havingconnecting air-intake and gas-mixing chambers; a slide-valve member,adjustably mounted between said chambers, and having a venturi-aperturemeans of variable flow area therethrough for passage of air from saidair-intake chamber to said gas-mixing chamber with correspondinglyvarying venturi effect on said air; means for adjusting said slide-valvemember to vary the effective flow area of said venturi aperture means;and a gas metering device presented within said gas-mixing chamber, forsupplying gas to said gasmixing chamber for convergence with said airpassed through said venturi aperture means, said relatively movableparts including a relatively fixed tube having therein a plurality ofgas metering holes, and a gas supply tube relatively movable withreference to said relatively fixed tube, to open and close one or moresaid holes to said gas mixing chamber, said'gas supply tube having a gasmixing chamber; and a tapered stem. being affixed to said housing toextend into said gas supply tube through said outlet orifice to vary theeffective gas flow area thereof in proportion to relative movement ofthe supply tube.

1. A carburetor as for a gasoline engine, comprising: a housing havingconnecting air-intake and gas-mixing chambers, a slidevalve member,adjustably mounted between said chambers, and having a venturi-aperturemeans of variable flow area therethrough, for passage of air from saidair-intake chamber to said gas-mixing chamber with correspondinglyvarying venturi effect on said air; means for adjusting said slide-valvemember to vary the flow area of said venturi aperture means, and a gasmetering device presented within said gas-mixing chamber, for supplyinggas to said gas-mixing chamber for convergence with said air passedthrough said venturi aperture means; said gas metering device includingrelatively movable parts to vary the supply of gas to said chamber, saidrelatively movable parts of the gas metering device including arelatively fixed tube having therein a plurality of gas metering holes,and a gas supply tube relatively movable with reference to saidrelatively fixed tube, to open and close one or more said gas meteringholes to said gas mixing chamber, said gas supply tube having a gasoutlet orifice in a free end thereof presented within said gas mixingchamber; and a tapered stem being affixed to said housing to extend intosaid gas supply tube through said outlet orifice to vary the effectivegas flow area thereof in proportion to relative movement of the supplytube.
 2. A carburetor as in claim 1, an air deflecting hood beingprovided above in said relatively fixed tube for dispersing the airpassing through said venturi-aperture means, and uniformly around thefixed tube.
 3. A carburetor as for a gasoline engine, comprising: ahousing having connecting air-intake and gas-mixing chambers; aslide-valve member, adjustably mounted between said chambers, and havinga venturi-aperture means of variable flow area therethrough for passageof air from said air-intake chamber to said gas-mixing chamber withcorrespondingly varying venturi effect on said air; means for adjustingsaid slide-valve member to vary the effective flow area of said venturiaperture means; and a gas metering device presented within saidgas-mixing chamber, for supplying gas to said gas-mixing chamber forconvergence with said air passed through said venturi aperture means,said relatively movable parts including a relatively fixed tube havingtherein a plurality of gas metering holes, and a gas supply tuberelatively movable with reference to said relatively fixed tube, to openand close one or more said holes to said gas mixing chamber, said gassupply tube having a gas mixing chamber; and a tapered stem beingaffixed to said housing to extend into said gas supply tube through saidoutlet orifice to vary the effective gas flow area thereof in proportionto relative movement of the supply tube.